/*
 * Copyright (c) 2006, Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the Contiki operating system.
 *
 */

/**
 * \file
 *         Callback timer implementation
 * \author
 *         Adam Dunkels <adam@sics.se>
 */

/**
 * \addtogroup ctimer
 * @{
 */

#include "sys/ctimer.h"
#include "contiki.h"
#include "lib/list.h"

LIST(ctimer_list);

static char initialized;

#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif

/*---------------------------------------------------------------------------*/
PROCESS(ctimer_process, "Ctimer process");
PROCESS_THREAD(ctimer_process, ev, data)
{
    struct ctimer *c;
    PROCESS_BEGIN();

    for(c = list_head(ctimer_list); c != NULL; c = c->next) {
        etimer_set(&c->etimer, c->etimer.timer.interval);
    }
    initialized = 1;

    while(1) {
        PROCESS_YIELD_UNTIL(ev == PROCESS_EVENT_TIMER);
        for(c = list_head(ctimer_list); c != NULL; c = c->next) {
            if(&c->etimer == data) {
                list_remove(ctimer_list, c);
                PROCESS_CONTEXT_BEGIN(c->p);
                if(c->f != NULL) {
                    c->f(c->ptr);
                }
                PROCESS_CONTEXT_END(c->p);
                break;
            }
        }
    }
    PROCESS_END();
}
/*---------------------------------------------------------------------------*/
void
ctimer_init(void)
{
    initialized = 0;
    list_init(ctimer_list);
    process_start(&ctimer_process, NULL);
}
/*---------------------------------------------------------------------------*/
void
ctimer_set(struct ctimer *c, clock_time_t t,
           void (*f)(void *), void *ptr)
{
    ctimer_set_with_process(c, t, f, ptr, PROCESS_CURRENT());
}
/*---------------------------------------------------------------------------*/
void
ctimer_set_with_process(struct ctimer *c, clock_time_t t,
                        void (*f)(void *), void *ptr, struct process *p)
{
    PRINTF("ctimer_set %p %u\n", c, (unsigned)t);
    c->p = p;
    c->f = f;
    c->ptr = ptr;
    if(initialized) {
        PROCESS_CONTEXT_BEGIN(&ctimer_process);
        etimer_set(&c->etimer, t);
        PROCESS_CONTEXT_END(&ctimer_process);
    } else {
        c->etimer.timer.interval = t;
    }

    list_add(ctimer_list, c);
}
/*---------------------------------------------------------------------------*/
void
ctimer_reset(struct ctimer *c)
{
    if(initialized) {
        PROCESS_CONTEXT_BEGIN(&ctimer_process);
        etimer_reset(&c->etimer);
        PROCESS_CONTEXT_END(&ctimer_process);
    }

    list_add(ctimer_list, c);
}
/*---------------------------------------------------------------------------*/
void
ctimer_restart(struct ctimer *c)
{
    if(initialized) {
        PROCESS_CONTEXT_BEGIN(&ctimer_process);
        etimer_restart(&c->etimer);
        PROCESS_CONTEXT_END(&ctimer_process);
    }

    list_add(ctimer_list, c);
}
/*---------------------------------------------------------------------------*/
void
ctimer_stop(struct ctimer *c)
{
    if(initialized) {
        etimer_stop(&c->etimer);
    } else {
        c->etimer.next = NULL;
        c->etimer.p = PROCESS_NONE;
    }
    list_remove(ctimer_list, c);
}
/*---------------------------------------------------------------------------*/
int
ctimer_expired(struct ctimer *c)
{
    struct ctimer *t;
    if(initialized) {
        return etimer_expired(&c->etimer);
    }
    for(t = list_head(ctimer_list); t != NULL; t = t->next) {
        if(t == c) {
            return 0;
        }
    }
    return 1;
}
/*---------------------------------------------------------------------------*/
/** @} */
